Low-cost strategies to scale back air air pollution from Bangladesh brick kilns new research

Bangladesh is without doubt one of the most polluted international locations on the earth. In accordance with an IQ Air evaluation, the nation had the second-worst air high quality in 2024 worldwide, with PM2.5 focus greater than 15-times the World Well being Organisation’s instructed restrict.

Brick kilns are a serious contributor to this air air pollution disaster. Earlier efforts to enhance the greenness of the native brick-making business have resulted in restricted success – but when a brand new research is to be believed, there’s room for low-cost interventions to make a distinction with these kilns.

Fastidiously crafted interventions

The research, revealed in Science on Could 8, was performed by researchers from the U.S., Bangladesh, and India. They carried out a randomised management trial involving 276 kilns in Bangladesh, within the brick-firing season of November to Could in 2022-2023.

The experiment had three components: one management arm and two interventions. One intervention was solely technical and the opposite included each a technical intervention and incentive info.

The principle concept behind the intervention arms of the trial was to scale back emissions, air air pollution, and gasoline prices whereas growing income by growing effectivity. Whereas each arms offered info, coaching, and technical help on environment friendly coal feeding and brick-stacking practices, the inducement info arm additionally guided staff with incentives in order that they caught to their newly discovered practices.

For the incentives, the researchers knowledgeable the kiln homeowners on numerous methods like bonuses, increased wages, and higher working situations that included meals, housing, and clothes, however left it as much as the homeowners and managers to resolve which strategy most closely fits their enterprise.

The staff additionally famous that the interventions have been cautious to not worsen the employees’ situations within the business, given the character of labor right here is usually precarious and exploitative.

The research was carried out on zigzag kilns – a reputation that refers back to the form of the stacks by which these kilns organize uncooked bricks, in order that extra scorching air is available in contact with the bricks’ surfaces. This technique improves warmth switch and will increase brick firing effectivity, and is the dominant sort of casual brick kiln working in Bangladesh, accounting for 81% of the sector.

No impact of incentives

The researchers additionally famous that the operators of most of those kilns have been receptive to the interventions and that 65% of the kilns adopted the really useful practices. Nearly 20% of management kilns (one other kiln sort) additionally did so, testifying to the demand.

Curiously, the researchers reported that whereas there have been no variations within the charges of adoption, the presence or absence of incentives didn’t have an impact both. That is in distinction to earlier research that discovered immediately offering financial incentives to staff may result in higher outcomes.

Among the many compliant kilns, researchers famous a 23% discount in vitality use, a 20% discount in each carbon dioxide and PM2.5 emissions, and higher brick high quality and decrease gasoline price per brick. The intervention’s advantages outweighed its prices by 65:1, with carbon dioxide reductions costing $2.85 per tonne.

Not one of the interventions wanted further capital funding.

No rebound results

The proof of how environment friendly energy-related interventions are has been inconsistent previously. Nonetheless, the brand new research has introduced substantial proof that fastidiously designed operational enhancements may also result in important vitality financial savings.

The 5 operational enhancements the research targeted on have been: single fireman steady gasoline feeding, improved brick stacking, a thicker ash layer on kiln prime, closing the kiln gate with a cavity wall, and complementary use of powdered biomass gasoline. The concept behind these particular modifications was that they enhance gasoline combustion and forestall lack of warmth within the kilns.

Notably, the vitality financial savings famous within the research have been achieved with out rebound results, which often negate the profit by growing vitality use elsewhere. The absence of those results makes a stronger case for these interventions, the researchers stated.

The decrease carbon dioxide and PM2.5 emissions noticed in the course of the trial experiment have essential public well being implications, particularly for a rustic like Bangladesh. In accordance with the researchers, if the mission is scaled nationally and the interventions are adopted by all 6,352 zigzag kilns in Bangladesh, carbon dioxide emissions could possibly be introduced down by 2.4 million metric tonnes in a single brick-firing season – round 2% of the nation’s annual emissions.

The researchers additionally expressed perception that their interventions may be scaled up throughout Bangladesh in addition to South Asia – a area with a major air air pollution drawback.

Brick manufacturing methods are related all through most South Asian international locations. Regulating vitality effectivity is especially helpful in these areas the place air air pollution has turn out to be a major problem in addition to the place vitality demand is growing quickly. In these areas, state intervention has typically proved an unreliable technique to management emissions, particularly in casual sectors.